// Well-designed REST API with proper status codes
import { Router, Request, Response } from 'express';

const router = Router();

router.get('/users/:id', async (req: Request, res: Response) => {
  const { id } = req.params;

  const user = await userService.findById(id);

  if (!user) {
    return res.status(404).json({
      error: {
        code: 'USER_NOT_FOUND',
        message: `User with id ${id} not found`,
      }
    });
  }

  return res.status(200).json({
    data: {
      id: user.id,
      name: user.name,
      email: user.email,
      createdAt: user.created_at.toISOString(),
    }
  });
});

router.post('/users', async (req: Request, res: Response) => {
  const { name, email, password } = req.body;

  // Validation
  if (!email || !name || !password) {
    return res.status(400).json({
      error: {
        code: 'VALIDATION_ERROR',
        message: 'name, email, and password are required',
        fields: {
          name: !name ? 'Required' : undefined,
          email: !email ? 'Required' : undefined,
        }
      }
    });
  }

  try {
    const user = await userService.create({ name, email, password });
    return res.status(201).json({ data: user });
  } catch (error) {
    if (error.code === 'EMAIL_EXISTS') {
      return res.status(409).json({
        error: { code: 'EMAIL_EXISTS', message: 'Email already in use' }
      });
    }
    throw error;
  }
});
API Design — REST, GraphQL, gRPC

API Design — REST, GraphQL, gRPC

API Design — REST, GraphQL, gRPC
